JPWO2013125213A1 - Imaging lens and imaging apparatus provided with the same - Google Patents

Abstract

In the imaging lens, small aberration, small F number, wide angle, good correction of various aberrations including chromatic aberration of magnification, and high optical performance are realized. The imaging lens includes, in order from the object side, a front group (GF) having a positive refractive power, a stop, and a rear group (GR) having a positive refractive power. The front group (GF) includes, in order from the object side, a negative meniscus lens (L1) having a convex surface directed toward the object side, a negative lens (L2), and a positive lens (L3). The rear group (GR) includes, in order from the object side, a positive lens (L4), a negative lens (L5), a positive lens (L6), and a positive lens (L7). When the Abbe numbers with respect to the d-line of the lens (L1) and the lens (L2) are ν1 and ν2, the following conditional expressions (1) and (2) are satisfied. 10.0 <ν2-ν1 (1) 40 <ν2 (2) [Selection] FIG.

Description

  The present invention relates to an imaging lens and an imaging apparatus including the imaging lens. More specifically, the imaging lens includes an imaging lens that can be suitably used for a digital camera, a broadcast camera, a surveillance camera, an in-vehicle camera, and the like, and the imaging lens. The present invention relates to an imaging device.

  In recent years, solid-state imaging devices mounted on cameras in the above fields have been downsized and the number of pixels has increased, and accordingly, downsizing and high performance of imaging lenses have been required. On the other hand, imaging lenses used for surveillance cameras, in-vehicle cameras, and the like are required to have a small F number and a wide angle.

  As an imaging lens that can be used with a solid-state imaging device, for example, a lens described in Patent Document 1 below is known. Patent Document 1 describes a seven-lens photographing lens including a front group having negative refractive power, a stop, and a rear group having positive refractive power. As wide-angle imaging lenses, for example, those described in Patent Documents 2 and 3 below are known. Patent Document 2 discloses a retrofocus lens having a front group including four lenses having positive refractive power, a stop, and a rear group including three lenses having positive refractive power. Have been described. In Patent Document 3, in order from the object side, two negative meniscus lenses having a convex surface facing the object side, a positive lens, a positive lens, a cemented lens of a negative lens, and two positive lenses are arranged. A lens system is described.

JP 2000-19391 A JP-A-7-218826 Japanese Patent Publication No. 4-16161

  However, the lens system described in Patent Document 1 has a large F number of 3.2 and a small angle of view of 64 °. The lens system described in Patent Document 2 has a small F number, but the total angle of view is about 85 °, which is not sufficient. Although the lens system described in Patent Document 3 has a small F number and a wide angle, the total length is about 8 times the focal length, and there is room for improvement in terms of performance. For example, when used in combination with a solid-state imaging device, it is required that chromatic aberration of magnification be corrected well.

  SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and an object of the present invention is to provide an imaging device that is small, has a small F-number, is wide-angle, has various optical aberrations including chromatic aberration of magnification, and has high optical performance. An object is to provide a lens and an imaging device including the imaging lens.

The imaging lens of the present invention is substantially composed of a front group having a positive refractive power, an aperture, and a rear group having a positive refractive power in order from the object side. Consists of a negative meniscus lens with a convex surface facing the object side, a negative lens, and a positive lens.The rear group consists of a positive lens, a negative lens, a positive lens, and a positive lens in order from the object side. Conditional expressions (1) and (2) are satisfied.
10.0 <ν2-ν1 (1)
40 <ν2 (2)
However,
ν1: Abbe number with respect to d line of negative meniscus lens ν2: Abbe number with respect to d line of second negative lens from the object side in the front group

In the imaging lens of the present invention, it is preferable that any one of the following conditional expressions (3) to (7) or any combination is satisfied.
0.30 <f / f1 <0.80 (3)
0.20 <f1 / f2 <1.30 (4)
0.20 <(R1-R2) / (R1 + R2) <0.60 (5)
0.90 <Dair / f <2.30 (6)
9.0 <(Navg−1.5) × νavg <13.0 (7)
f: focal length of the entire system f1: focal length of the front group f2: focal length of the rear group R1: radius of curvature of the object side surface of the negative meniscus lens closest to the object side in the front group R2: closest object side of the front group Radius of curvature of image side surface of negative meniscus lens Dair: longest air interval in the entire system Navg: average refractive index νavg for all lenses in the entire system νavg: Abbe relative to d-lines of all lenses in the entire system Number average

Furthermore, in the imaging lens of the present invention, it is more preferable that the following conditional expressions (1 ′) to (7 ′) are satisfied instead of the conditional expressions (1) to (7).
15.0 <ν2-ν1 (1 ')
56 <ν2 (2 ')
0.30 <f / f1 <0.60 (3 ′)
0.50 <f1 / f2 <1.10 (4 ′)
0.25 <(R1-R2) / (R1 + R2) <0.40 (5 ')
1.0 <Dair / f <2.0 (6 ′)
10.0 <(Navg−1.5) × νavg <11.0 (7 ′)

  In the imaging lens of the present invention, it is preferable that the first positive lens and the second negative lens are cemented from the object side of the rear group.

  In the imaging lens of the present invention, it is preferable that the total angle of view is larger than 90 °.

  In addition, “substantially” in the above “substantially composed of” means a lens having substantially no power, other than a lens such as an aperture, a cover glass, a filter, etc. in addition to the above-described constituent requirements. It is intended that an optical element, a lens flange, a lens barrel, an image pickup device, a mechanism portion such as a camera shake correction mechanism, and the like may be included.

  Note that the lens surface shape, the sign of refractive power, and the radius of curvature in the imaging lens of the present invention described above are considered in the paraxial region when an aspheric surface is included. The sign of the radius of curvature is positive when the surface shape is convex on the object side and negative when the surface shape is convex on the image side.

  The imaging device of the present invention is characterized by including the imaging lens of the present invention.

  According to the present invention, in the lens system in which the positive front group, the stop, and the positive rear group are arranged in order from the object side, the entire system is configured by seven lenses, and the front group and the rear group are configured. Since the lens power array is set in detail and configured so as to satisfy a predetermined conditional expression, it is small, F-number is small, wide angle, and various aberrations including lateral chromatic aberration are corrected well. An imaging lens having high optical performance and an imaging device including the imaging lens can be provided.

Sectional drawing which shows the structure of the imaging lens of Example 1 of this invention Sectional drawing which shows the structure of the imaging lens of Example 2 of this invention Sectional drawing which shows the structure of the imaging lens of Example 3 of this invention. 4A to 4E are aberration diagrams of the imaging lens of Example 1 of the present invention. FIGS. 5A to 5E are aberration diagrams of the imaging lens of Example 2 of the present invention. 6A to 6E are aberration diagrams of the image pickup lens of Example 3 of the present invention. The figure for demonstrating arrangement | positioning of the imaging device concerning embodiment of this invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 are cross-sectional views illustrating the configuration of an imaging lens according to an embodiment of the present invention, and correspond to Examples 1 to 3 described later, respectively. 1 to 3, the left side is the object side, and the right side is the image side. Since the basic configuration and the illustration method of the example shown in FIGS. 1 to 3 are the same, the following description will be given mainly with reference to the configuration example shown in FIG.

  The imaging lens 1 according to the embodiment of the present invention includes, in order from the object side along the optical axis Z, a front group GF having a positive refractive power as a whole, an aperture stop St, and a rear having a positive refractive power as a whole. This is a fixed focus optical system in which the groups GR are arranged. Note that the aperture stop St shown in FIG. 1 does not necessarily indicate the size or shape, but indicates the position on the optical axis Z. The front group GF of the imaging lens 1 of the example shown in FIG. 1 includes lenses L1 to L3 arranged in order from the object side, and the rear group GR includes lenses L4 to L7 arranged in order from the object side.

  When the imaging lens is mounted on the imaging device, the imaging device is appropriately provided with a cover glass for protecting the imaging device and various filters such as a low-pass filter and an infrared cut filter according to the specifications of the imaging device. FIG. 1 shows an example in which a parallel plate-like optical member PP assuming these is arranged between the lens surface closest to the image side and the image plane Sim.

  In FIG. 1, the imaging element 5 disposed on the image plane Sim of the imaging lens 1 is also illustrated in consideration of the case where the imaging lens 1 is applied to an imaging apparatus. In FIG. 1, the image pickup device 5 is illustrated in a simplified manner, but actually, the image pickup surface of the image pickup device 5 is disposed so as to coincide with the position of the image plane Sim. The imaging element 5 captures an optical image formed by the imaging lens 1 and converts it into an electrical signal. For example, a CCD (Charge Coupled Device), a CMOS (Complementary Metal Oxide Semiconductor), or the like can be used.

  In the imaging lens 1 of the present embodiment, the front group GF is composed of a negative meniscus lens having a convex surface directed toward the object side, a negative lens, and a positive lens in order from the object side, and the rear group GR is sequentially formed from the object side. And a positive lens, a negative lens, a positive lens, and a positive lens.

  By making both the front group GF and the rear group GR positive lens groups, the overall length of the lens system can be shortened. Further, by disposing the aperture stop St substantially in the middle of the lens system, it is possible to reduce the lens diameter while suppressing the light beam height at the most object side lens and the most image side lens where the light beam height tends to be high.

  Disposing a negative meniscus lens having a convex surface facing the object side closest to the object side of the entire system is advantageous for widening the angle. Further, the power array in the front group GF is made negative, negative, and positive retrofocus types in order from the object side, which is further advantageous for widening the angle.

  In the rear group GR, the most object-side lens, that is, the lens L4 immediately after the image side of the aperture stop St is a positive lens, so that the light flux that tends to spread through the aperture stop St can be converged. This is advantageous for downsizing. By arranging two positive lenses on the most image side of the entire system, the positive refractive power of the rear group GR can be shared, which is advantageous for good correction of spherical aberration.

  The second lens from the object side of the front group GF may be a plano-concave lens or a negative meniscus lens. The lens closest to the image side of the front group GF is preferably a biconvex lens in order to ensure the positive refractive power necessary for the front group GF while having a small size.

  It is preferable that the first positive lens and the second negative lens are cemented from the object side of the rear group GR. In the example shown in FIG. 1, the lens L4 and the lens L5 are cemented. By joining these, axial chromatic aberration can be corrected well without deteriorating various aberrations. The first and second lenses from the object side of the rear group GR are preferably a biconvex lens and a biconcave lens, respectively.

The imaging lens 1 of the present embodiment is configured to satisfy the following conditional expressions (1) and (2).
10.0 <ν2-ν1 (1)
40 <ν2 (2)
However,
ν1: Abbe number with respect to d line of the negative meniscus lens closest to the object side in the front group ν2: Abbe number with respect to d line of the second negative lens from the object side in the front group

  If the lower limit of conditional expression (1) is not reached, chromatic aberration of magnification in the blue wavelength region such as F-line (wavelength 486.13 nm) tends to be over. If the lower limit of conditional expression (2) is reached, the chromatic aberration of magnification in the blue wavelength region such as the F line tends to be under. By configuring the Abbe number of the first and second lenses from the object side where the ray height of off-axis rays is high so as to satisfy the conditional expressions (1) and (2), the chromatic aberration of magnification can be satisfactorily corrected. It becomes possible.

Furthermore, it is preferable that the imaging lens of the present embodiment satisfies any one of the following conditional expressions (3) to (7), or any combination. It is preferable to appropriately and appropriately have the configuration described below according to matters required for the imaging lens.
0.30 <f / f1 <0.80 (3)
0.20 <f1 / f2 <1.30 (4)
0.20 <(R1-R2) / (R1 + R2) <0.60 (5)
0.90 <Dair / f <2.30 (6)
9.0 <(Navg−1.5) × νavg <13.0 (7)
f: focal length of the entire system f1: focal length of the front group f2: focal length of the rear group R1: radius of curvature of the object side surface of the negative meniscus lens closest to the object side in the front group R2: closest object side of the front group Radius of curvature of image side surface of negative meniscus lens Dair: longest air interval in the entire system Navg: average refractive index νavg for all lenses in the entire system νavg: Abbe relative to d-lines of all lenses in the entire system Number average

  If the lower limit of conditional expression (3) is not reached, the total length of the lens system becomes longer. If the upper limit of conditional expression (3) is exceeded, it will be difficult to widen the angle of view. Satisfying conditional expression (3) is advantageous in constructing a wide angle while suppressing the overall length.

  If the lower limit of conditional expression (4) is not reached, it is difficult to widen the angle of view. If the upper limit of conditional expression (4) is exceeded, the total length becomes longer. By satisfying conditional expression (4), it is advantageous to balance the refractive powers of the front group GF and the rear group GR and to form a wide angle while suppressing the total length.

  If the lower limit of conditional expression (5) is not reached, spherical aberration tends to be over. If the upper limit of conditional expression (5) is exceeded, spherical aberration tends to be under and it becomes difficult to correct axial chromatic aberration. Satisfying conditional expression (5) is advantageous for good correction of spherical aberration and axial chromatic aberration.

  If the lower limit of conditional expression (6) is not reached, an optical system having a large F number or an optical system having a small angle of view is obtained. If the upper limit of conditional expression (6) is exceeded, the total length of the lens system becomes long, or it becomes difficult to satisfactorily correct various aberrations.

  Note that the air distance of Dair in conditional expression (6) is the distance between adjacent lens surfaces with air sandwiched therebetween. In order to realize a wide angle and good aberration correction while configuring a small size with a small number of lenses, the longest air interval in the entire system is between the lens L2 and the lens L3 as in the example shown in FIG. It is preferable to do.

  If the lower limit of conditional expression (7) is not reached, spherical aberration and axial chromatic aberration tend to be over. When the upper limit of conditional expression (7) is exceeded, spherical aberration tends to be under or chromatic aberration of magnification tends to be over.

From the above circumstances, it is more preferable that the following conditional expressions (1 ′) to (7 ′) are satisfied instead of the conditional expressions (1) to (7).
15.0 <ν2-ν1 (1 ')
56 <ν2 (2 ')
0.30 <f / f1 <0.60 (3 ′)
0.50 <f1 / f2 <1.10 (4 ′)
0.25 <(R1-R2) / (R1 + R2) <0.40 (5 ')
1.0 <Dair / f <2.0 (6 ′)
10.0 <(Navg−1.5) × νavg <11.0 (7 ′)

  In addition, the imaging lens of the present embodiment is preferably configured so that the total angle of view is greater than 90 °. As a result, it can be suitably used for surveillance cameras, in-vehicle cameras, and the like that require a wide field of view.

Next, numerical examples of the imaging lens of the present invention will be described.
[Example 1]
A lens sectional view of the imaging lens of Example 1 is shown in FIG. Since the method of illustration is as described above, duplicate explanation is omitted here.

  The schematic configuration of the imaging lens of Example 1 is as follows. That is, in order from the object side, the front group GF having a positive refractive power, an aperture stop St, and a rear group GR having a positive refractive power. The front group GF is convex from the object side to the object side. The negative meniscus lens L1 facing the lens, the plano-concave lens L2 facing the plane toward the object side, and the biconvex lens L3, and the rear group GR has a biconvex shape in order from the object side. The lens L4 includes a biconcave lens L5, a biconvex lens L6, and a biconvex lens L7. The lens L4 and the lens L5 are cemented, and the other lenses are single lenses that are not cemented. All of the lenses L1 to L7 are spherical lenses.

  As a detailed configuration of the imaging lens of Example 1, Table 1 shows lens data, and Table 2 shows specifications. In Table 1, the column of Si indicates the i-th (i = 1, 2, 3,...) Surface number that sequentially increases toward the image side with the object-side surface of the most object-side component being first. The Ri column indicates the radius of curvature of the i-th surface. The sign of the radius of curvature is positive when the surface shape is convex on the object side and negative when the surface shape is convex on the image side. Further, the column of Di indicates the surface interval on the optical axis Z between the i-th surface and the i + 1-th surface. The bottom column of the column of Di is the surface interval between the most image side surface and the image surface Sim shown in Table 1.

  In Table 1, the Ndj column indicates the d-line (wavelength: 587.56 nm) of the j-th (j = 1, 2, 3,...) Optical element that sequentially increases toward the image side with the most object-side component being the first. ) And the column νdj indicates the Abbe number of the j-th optical element with respect to the d-line. The lens data includes the aperture stop St and the optical member PP, and the surface number and the phrase (St) are described in the surface number column of the surface corresponding to the aperture stop St.

  Table 2 shows the specifications of the imaging lens of Example 1. In Table 2, f is the focal length of the entire system, Bf is the back focus (air equivalent length), FNo. Is the F number, and ω is the half angle of view. The values shown in Table 2 are for the d line.

  In the following tables, degrees are used as the unit of angle, and mm is used as the unit of length. However, since the optical system can be used even with proportional enlargement or reduction, other suitable units are used. It is also possible to use it. In the following tables, numerical values rounded by a predetermined digit are described.

  Table 7 below shows the corresponding values of conditional expressions (1) to (7) of the imaging lens of Example 1 together with those of other Examples 2 and 3.

  4A to 4E show respective aberration diagrams of the spherical aberration, the sine condition violation amount, astigmatism, distortion (distortion), and lateral chromatic aberration (chromatic aberration of magnification) of the imaging lens of Example 1. Indicates. FNo. In the diagram of spherical aberration and sine condition violation amount. Means F value, and ω in other aberration diagrams means half angle of view. Each aberration diagram shows aberration with d-line (587.56 nm) as a reference wavelength, while spherical aberration diagram shows C-line (wavelength 656.27 nm), F-line (wavelength 486.13 nm), g-line ( The aberration for wavelength 435.84 nm is also shown, and the chromatic aberration diagram for magnification shows the aberration for C line and F line. In the astigmatism diagram, the sagittal direction is indicated by a solid line, and the tangential direction is indicated by a dotted line. 4A to 4E are those when the object distance is infinity.

  The illustration method, symbols, meanings, and description methods in the tables of Example 1 above are the same as in Examples 2 and 3 below unless otherwise specified, and therefore, repeated explanation is omitted below. To do.

[Example 2]
A lens cross-sectional view of the imaging lens of Example 2 is shown in FIG. The schematic configuration of the imaging lens of Example 2 is that Example 1 except that the lens L2 has a negative meniscus shape with a convex surface facing the object side, and the lens L6 has a positive meniscus shape with a convex surface facing the image side. Is the same as Tables 3 and 4 show lens data and specifications of the imaging lens of Example 2, respectively. 5A to 5E show aberration diagrams of the imaging lens of Example 2. FIG.

[Example 3]
A lens cross-sectional view of the imaging lens of Example 3 is shown in FIG. The schematic configuration of the imaging lens of Example 3 is the same as in Example 1 except that the lens L6 has a plano-convex shape with the plane facing the object side, and the lens L7 has a plano-convex shape with the plane facing the image side. Is the same as Tables 5 and 6 show lens data and specifications of the imaging lens of Example 3, respectively. 6A to 6E show aberration diagrams of the imaging lens of Example 3. FIG.

  Table 7 shows corresponding values of conditional expressions (1) to (7) of the imaging lenses of the first to third embodiments. The values shown in Table 7 are based on the d line.

  As can be seen from the above data, the imaging lenses of Examples 1 to 3 are composed of seven lenses, are small in size, can be manufactured on a full spherical surface at low cost, and have an F number as small as 2.0. While achieving a wide angle of view of 100 ° or more, various aberrations including chromatic aberration are well corrected and high optical performance is achieved. These imaging lenses can be suitably used for surveillance cameras, in-vehicle cameras for taking images of the front, side, rear, etc. of automobiles.

  As an example of use, FIG. 7 illustrates a state in which an imaging apparatus including the imaging lens of the present embodiment is mounted on the automobile 100. In FIG. 7, an automobile 100 includes an in-vehicle camera 101 for imaging a blind spot range on the side surface on the passenger seat side, an in-vehicle camera 102 for imaging a blind spot range on the rear side of the automobile 100, and a rear surface of a rearview mirror. An in-vehicle camera 103 is attached and is used for photographing the same field of view as the driver. The vehicle exterior camera 101, the vehicle exterior camera 102, and the vehicle interior camera 103 are imaging devices according to the embodiment of the present invention. An imaging lens according to the embodiment of the present invention and an optical image formed by the imaging lens are used as electrical signals. An image sensor for conversion.

  The present invention has been described with reference to the embodiments and examples. However, the present invention is not limited to the above embodiments and examples, and various modifications can be made. For example, the values of the radius of curvature, the surface spacing, the refractive index, the Abbe number, etc. of each lens are not limited to the values shown in the above numerical examples, but can take other values.

  Further, in the embodiment of the imaging device, the present invention has been described with reference to an example of a camera mounted on a four-wheeled vehicle. However, the present invention is not limited to this application, for example, for a two-wheeled vehicle. It can also be applied to in-vehicle cameras, mobile terminal cameras, surveillance cameras, and the like.

The imaging lens of the present invention is substantially composed of a front group having a positive refractive power, an aperture, and a rear group having a positive refractive power in order from the object side. a negative meniscus lens having a convex surface directed toward the object side, a negative lens, and a positive lens, the rear group includes, in order from the object side, a positive lens, a negative lens, a positive lens, and a positive lens, the total The angle of view is larger than 90 °, and the following conditional expressions (1) and (2) are satisfied.
10.0 <ν2-ν1 (1)
40 <ν2 (2)
However,
ν1: Abbe number with respect to d line of negative meniscus lens ν2: Abbe number with respect to d line of second negative lens from the object side in the front group

4A to 4E show respective aberration diagrams of the spherical aberration, the sine condition violation amount, astigmatism, distortion (distortion), and lateral chromatic aberration (chromatic aberration of magnification) of the imaging lens of Example 1. Indicates. FNo. In the diagram of spherical aberration and sine condition violation amount. Means F value, and ω in other aberration diagrams means half angle of view. Each aberration diagram shows aberration with d-line ( wavelength 587.56 nm) as a reference wavelength, while spherical aberration diagram shows C-line (wavelength 656.27 nm), F-line (wavelength 486.13 nm), g-line. The aberration for (wavelength 435.84 nm) is also shown, and the chromatic aberration diagram for magnification shows the aberration for the C line and F line. In the astigmatism diagram, the sagittal direction is indicated by a solid line, and the tangential direction is indicated by a dotted line. 4A to 4E are those when the object distance is infinity.

Claims (16)

In order from the object side, it is substantially composed of a front group having a positive refractive power, a stop, and a rear group having a positive refractive power,
The front group includes, in order from the object side, a negative meniscus lens having a convex surface facing the object side, a negative lens, and a positive lens.
The rear group, in order from the object side, consists of a positive lens, a negative lens, a positive lens, and a positive lens,
An imaging lens satisfying the following conditional expressions (1) and (2):
10.0 <ν2-ν1 (1)
40 <ν2 (2)
However,
ν1: Abbe number with respect to d line of the negative meniscus lens ν2: Abbe number with respect to d line of the second negative lens from the object side of the front group The imaging lens according to claim 1, wherein the following conditional expression (1 ′) is satisfied.
15.0 <ν2-ν1 (1 ') The imaging lens according to claim 1, wherein the following conditional expression (2 ′) is satisfied.
56 <ν2 (2 ') The imaging lens according to any one of claims 1 to 3, wherein the following conditional expression (3) is satisfied.
0.30 <f / f1 <0.80 (3)
However,
f: focal length of the entire system f1: focal length of the front group The imaging lens according to claim 4, wherein the following conditional expression (3 ′) is satisfied.
0.30 <f / f1 <0.60 (3 ′) The imaging lens according to claim 1, wherein the following conditional expression (4) is satisfied.
0.20 <f1 / f2 <1.30 (4)
However,
f1: Focal length of the front group f2: Focal length of the rear group The imaging lens according to claim 6, wherein the following conditional expression (4 ′) is satisfied.
0.50 <f1 / f2 <1.10 (4 ′) The imaging lens according to claim 1, wherein the following conditional expression (5) is satisfied.
0.20 <(R1-R2) / (R1 + R2) <0.60 (5)
However,
R1: radius of curvature of the object side surface of the negative meniscus lens R2: radius of curvature of the image side surface of the negative meniscus lens The imaging lens according to claim 8, wherein the following conditional expression (5 ′) is satisfied.
0.25 <(R1-R2) / (R1 + R2) <0.40 (5 ') The imaging lens according to claim 1, wherein the following conditional expression (6) is satisfied.
0.90 <Dair / f <2.30 (6)
However,
Dair: longest air gap in the entire system f: focal length of the entire system The imaging lens according to claim 10, wherein the following conditional expression (6 ′) is satisfied.
1.0 <Dair / f <2.0 (6 ′) The imaging lens according to claim 1, wherein the following conditional expression (7) is satisfied.
9.0 <(Navg−1.5) × νavg <13.0 (7)
However,
Navg: average refractive index of all lenses in the entire system with respect to the d-line νavg: average of Abbe numbers with respect to the d-line of all lenses in the entire system The imaging lens according to claim 12, wherein the following conditional expression (7 ′) is satisfied.
10.0 <(Navg−1.5) × νavg <11.0 (7 ′)   The imaging lens according to any one of claims 1 to 13, wherein a first positive lens and a second negative lens from the object side of the rear group are cemented.   The imaging lens according to claim 1, wherein the total angle of view is greater than 90 °.   An imaging apparatus comprising the imaging lens according to claim 1.

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